Recap: The issue is that a small parachute was seen floating back to the ocean within a minute of the break-up of Space Shuttle Challenger. What was that parachute carrying? Bara says it was the entire crew cabin; that the crew survived and are now living new lives.
In my 2nd November piece, I showed this timeline from Spaceflight Now, as refutation of Bara's theory.
Somebody obviously showed Bara that timeline, because he read it out during yesterday's "Tell The Truth Wednesday" vlog. At 15:34 Bara continued:
"They're saying then that there's a separate system where both the cap and the SRB had a... had a drogue parachute. I question that, because I don't remember that ever being in the design. I'll have to go back and look at the design of the Space Shuttle, um.. Challenger.. the Shuttle SRBs, find out if that was the case. I kind-of don't think that was the case. Logically it doesn't make a lot of sense, because, you know, the cap is much smaller—the SRBs land in the ocean, and are recovered. They're much easier to find... I don't know how you find... The SRB caps were only about...Oh, six feet across, maybe, no more than that. Maybe ten feet, I'll have to look that up again, but they weren't very big, and, y'know, finding a cap, a metal cap or something like that, they'd be real cheap and probably easy to replace. Actually it would really surprise me if there was a recovery system for them."Frustum
I decided to dig a little deeper, and went looking for a technical paper on SRB design. What I found was a NASA technical news reference, including this nice exploded view of the SRB components.
Immediately below the nose cap is a section called the frustum (that's just the word for a truncated cone in solid geometry). The frustum contains instrumentation in addition to all the gubbins required to pull the pilot 'chute, the drogue 'chute, and finally the main parachutes, out of their stowed configuration. Immediately below the frustum is a ring containing the Frustum Location Aids. The text of this technical paper, edited, with emphasis added, reads as follows:
"After burnout, the forward assembly initiates the release of the nose cap and frustum and turns on the recovery aids. ... Location aids are provided for each SRB, frustum/ drogue chutes and main parachutes. These include a transmitter, antenna, strobe/ converter, battery and salt water switch electronics. The location aids are designed for a minimum operating life of 72 hours and when refurbished are considered usable up to 20 times. ...The SRB nose caps and nozzle extensions are not recovered. The recovery crew retrieves the SRBs, frustum/ drogue chutes, and main parachutes."So there you have it. The baby parachute was carrying, not the nose cone but the frustum. Bara was right on one point—that the nose caps were not worth recovering. But there's the answer to his question "I don't know how you find [something like that]." By the way, the diameter of the SRBs was 12.17 feet (3.7m.)
Bottom line—it wasn't the crew cabin. The crew all died.
Bara was wrong, but was Spaceflight Now also wrong?
Maybe, maybe not. That's certainly the implication of that paragraph at T+76.437. But read it again. It says that the nose cap separates and the drogue parachute deploys, which is correct. Then it says "A lone parachute seen emerging from the plume of a SRB." You immediately assume it's the nose cap under that 'chute. But the timeline doesn't actually say that. I think Spaceflight Now is off the hook. Bara is still very much on it.
Update 20 November:
Just to ram home the point, here's a photo of the actual frustum of STS-51L, after recovery. And here's the undamaged frustum from STS-87, on its way to refurb/re-use.
No comments:
Post a Comment